This invention relates to an apparatus for measuring flow in a break between ends of a fluid line and a method for accomplishing same; and more particularly relates to a novel and improved apparatus and method for measuring fluid that requires minimal separation in a fluid line.
Water usage in an agricultural setting typically requires the installation of metering devices in the field. Various agencies are offering cost-share programs, making use of water metering devices more desirable if not mandatory. Use of a water meter device aids in accurate metering of water for conservation purposes as well as for regulation purposes. Installation of metering devices typically requires retrofitting the user's current water transport system. Agricultural water meter systems require a specified linear distance between a water line and a water metering device to avoid improper readings due to turbulence, vortices, jetting, cavitations and other fluid flow disruptions. Most agricultural water meters require 48″ to 96″ of space for proper metering. This requirement means upstream straight pipe recommendations of 10 to 30 diameters of pipe, 5 diameters minimum when straightening vanes are use. While the velocity profile of water through a straight pipe remains fairly constant, in an irrigation line, check valves and elbows produce turbulent flow. Turbulent flow forces users to install meter housing devices with extensive pipeline configurations and long upstream straight runs in order to accommodate a water meter and obtain accurate readings. Oftentimes, the linear space that is available for installing a water meter device is insufficient and this results in a user having to run an extensive amount of piping in order to accommodate the water meter. Currently, users are forced to dig open pits for placement of the pipeline and reinstall a longer piece of pipe or adding at least 48″ of straight pipe above ground to accommodate a water meter. This requires substantial cost for backhoe work and labor to reconnect the fittings. Also, there is a risk of damage to the existing structures as well.
A combination of a water flow conditioning device and a meter housing is needed to conveniently and economically measure water flow. Of the flow conditioning units presently in use, straightening vanes or guide vanes are disposed along the flow line to minimize turbulence and regulate flow distribution within a pipe section. A number of devices have been developed for conditioning the flow of fluid for measurement. Representative of such devices are set forth in U.S. Pat. No. 2,929,248 to Sprenkle, U.S. Pat. No. 4,821,768 to Lett and U.S. Pat. No. 5,323,661 to Cheng. Although these devices aid in conditioning fluid flow in a pipeline, none of these address the problem solved by applicant's invention.
There is a need for an apparatus that solves the current problem facing agricultural water users, accommodating a meter device in a limited space while still providing accurate measurement of fluid flow. The combination of straightening or guide vanes, elbow sections and an equalization pipe provides for a novel apparatus that reduces the distance of flow separation or breaks in a fluid line in such a way that turbulence and distribution of the fluid are reduced while accurate measurement of the fluid is accomplished. The present invention insures a full pipe flow absent air, jetting, turbulence, vortices, cavitations and other velocity disruptions that increase friction resulting in obstruction of the laminar flow of fluids.